Mini Combustion Problems

[Vincente]

My simple mini combustion isn't working properly. It consists of:

1 Film Canister as the chamber
1 Film Canister lid and pen tube (connected) as the barrel
2 Nails for spark jumping
1 Piezo for spark

The peizo is attached to the nails via wires and alligator clips (heat sinks).
The peizo sparks almost every time. I use Tag deoderant spray as fuel. The gun has fired twice with the barrel on, and has had a quiet report. The gun has fired twice with the barrel off also, and blue flames came out of the chamber and the film canister became warm.

To fire, I spray a short burst of Tag into the chamber, put the barrel on as fast as I can, and click the piezo. I have tried to fire many times but it has only worked four times (see above). I think it has to do with the fuel to oxygen ratio but I can't be sure as this is my first mini combustion. Can anyone help me make my mini work?

(Sorry for the long post but I tried to post all info possible on my mini to avoid anyone posting asking for more details.)

EDIT: To give as much information possible on my mini, I must say that all of the shots that I fired were the first shots of the days that I shot them on. I shot four working shots over the four days after the cannon was built. Therefore, all of the first shots worked, and all of the shots after them didn't work. This leads me to believe that condensation could be an issue?

TOPIC MOVED TO GENERAL AFTER BEING REQUESTED TO DO SO BY THE POSTER-PIMPMANN22

[Torch]

Did you try waving it around a few times without the cap on? I do that to mine to get the fuel mixed with O2 and it works almost everytime. You could also try using some butine (cant spell very well ) from lighters and such.

[Vincente]

Yeah I've tried that. Do I do that after I spray the Tag in or before? I've done that after and it didn't work.

I'm starting to think that condensation could be the issue. Should I wipe the chamber out after every shot?

[Torch]

I would clean it out like after every 25 shots or somesuch. Try blowing into it to vent spent fumes out?

[Vincente]

OK thanks I'll try that tomorrow and get back to you. I've had enough aggravation from this mini for one day.